Answer
The word dominion means “rule or power over.” God has sovereign power over His creation and has delegated the authority to mankind to have dominion over the animals (Genesis 1:26). David reinforces this truth: “You made [mankind] rulers over the works of your hands; you put everything under their feet” (Psalm 8:6). Humanity was to "subdue" the earth (Genesis 1:28)—we were to hold a position of command over it; we were placed in a superior role and were to exercise control over the earth and its flora and fauna. Mankind was set up as the ruler of this world. All else was subjugated to him.
God’s command to subdue the earth and the animal life in it is a command to have the mastery over all of it. A true mastery (of anything) cannot be accomplished without an understanding of the thing mastered. In order for a musician to master the violin, he or she must truly understand the instrument. In order for mankind to attain mastery over the animal kingdom, we must understand the animals.
With the authority to rule comes the responsibility to rule well. There is an inherent accountability in the command to subdue the earth. Man has a duty to exercise his dominion under the authority of the One who delegated it. All authority is of God (Romans 13:1-5), and He delegates it to whomever He will (Daniel 4:17). The word subdue doesn’t have to imply violence or mistreatment. It can mean “to bring under cultivation.”
Man is to be the steward of the earth; he is to bring the material world and all of its varied elements into the service of God and the good of mankind. The command to subdue the earth is actually part of God’s blessing on mankind. Created in the image of God, Adam and Eve were to use the earth’s vast resources in the service of both God and themselves. It would only make sense for God to decree this, since only humans were created in God’s image.
When God gave humanity dominion over the animals, it was in order to care for, tend to, and use those animals to their fullest potential in a just manner. At the time that God gave mankind dominion over the animals, humans did not eat meat (Genesis 1:29). Eating meat did not begin until after the Flood (Genesis 9:1–3), and it was at that time that animals started to fear humans. However, although God changed the way we interact with animals, in that they are now “meat,” we still bear a responsibility to treat animals humanely. Human rule over animals does not mean we have the right to mistreat or misuse those animals.
Having dominion over the animals should entail a humane management of them as the resource God has ordained them to be. We should consider that mankind was given the task (and blessing) of representing God in this world. We are the caretakers. We hold sway over all the earth, and we (bearing God’s image) bear a responsibility to act as God would. Does God misuse His creation? No. Is God unwise in His management of resources? No. Is God ever cruel or selfish or wasteful? No. Then neither should we be. Any misuse or mistreatment of God’s creation is the result of sin, not the result of following God’s original command. We must fulfill our duty to manage the earth wisely until that time when the wolf shall lie down with the lamb in the kingdom of Christ (Isaiah 11:6).